The present invention relates to a method for increasing the measuring accuracy for a limited path using a measuring system.
A sensor for scanning a scale in order to measure a relevant distance or a position along a path is known from the related art—for example from three-coordinate measuring machines. Since the scale is in the form of a ruled grid, after such a measuring machine is turned on, the sensor must first move to a zero position, at which the applicable coordinates in a counter and/or a display device are then set to zero. If the measuring machine now travels in the direction of this coordinate, the lines of the scale—known as path events—are counted. Since the lines of the grid generally do not correspond to the usual specification in millimeters, the electrical signal of the sensor is converted into the applicable unit.
Measuring by using a grid or line scale is in some cases not merely counting off these lined bars. For example, there is the method that by using a second lined bar that moves together with the measuring device, a moiré pattern is created. This moiré pattern is then interpreted by the sensor and fed to a converter which converts it into the applicable unit of measurement.
In order to achieve high precision with the measuring systems from the related art, high accuracy of the scale is also always necessary. Naturally the accuracy of a sensor also plays a part, but no matter how precise a sensor may be, without a precise scale—which embodies a measuring system—precise measuring is not possible.